This invention relates to a process for manufacturing a body structure for a vehicle, particularly a convertible, which has a transversely extending rear wall in the area of the rearward wheel houses connected to the bottom and the wheel houses, the rear wall being supported on forward body structure by way of longitudinally directed, laterally exterior members.
In the case of a known body structure of the initially mentioned type (for example, the new Daimler-Benz Roadster, Model 129 described in an article "The New Mercedes-Benz Roadster--Body: Passive Safety" in ATZ 91 (1989)5, Pages 227 to 235), the rear wall, including the two longitudinally directed, laterally exterior members, is mounted during the manufacturing of the shell and is welded to the adjoining body parts. The rear wall and the longitudinally directed members are made of steel plate and therefore have a relatively high weight. After the manufacturing of the shell, the whole body structure is subjected to surface treatments of prime-coating and painting.
It is an object of the invention to provide a process for manufacturing a body structure for a convertible in which cost and weight are saved and the processing time during the shell manufacturing is reduced.
According to the invention, this object is achieved by a process for manufacturing, comprising forming a prefabricated module separate from remaining body structure, which prefabricated module includes the rear wall and two longitudinally directed laterally exterior members, surface treating the remaining body structure, and subsequently connecting the prefabricated module to the remaining body structure.
Principal advantages achieved by means of the invention are that, by separating a part of the structure (rear wall module) from the shell manufacturing and by forming a prefabricated, easily mountable module, costs are reduced in the manufacturing of the shell because high-expenditure welding operations of the rear wall are no longer required. At the same time, the processing time during the manufacturing of the shell is reduced considerably. The investment costs are also reduced. The combining of shell components in a subassembly and the manufacturing in light metal or plastic results in a considerable reduction of weight of up to 25%.
The module containing the rear wall in certain preferred embodiments also contains other components, such as three-point seat belts, rollover protection devices, loudspeakers, cover locks, seals, and the like, in which case the complete module may be furnished as a preassembled unit from an external supplier.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.